Asphalt compacting machine



Nov. 17, 1953 J. H. LUCAS ASPHALT COMPACTING MACHINE 5 Sheets-Sheet 1 Filed Dec. 24, 1949 Jack .72; La cas BY Mi: W

ATTORNEYS MW Q Nov. 17, 1953 J. H. LUCAS ASPHALT COMPACTING MACHINE 3 Sheets-Sheet 2 Filed Dec. 2.4, 1949 0 mm v m. mm mm N mvzwron Jack fLLu'c;

ATTORNEYS Nov. 17, 1953 J. H. LUCAS ASPHALT COMPACTING MACHINE 3 Sheets-Sheet 3 Filed Dec. 24, 1949 INVENTOR Jack Ji. La c'as mi: rwwi/ ATTORNEYS Patented Nov. 17, 1953 UNITED STATES PATENT OFFICE ASPHALT COMPACTING MACHINE Jack H. Lucas, Stockton, Calif.

Application December 24, 1949, Serial No. 134,929

1 Claim. 1

This invention has for an object the provision of a relatively small, mobile asphalt compacting machine for tamping and rolling fresh asphalt close to walls, curbs, or the like; the machine being self-propelled, but of walk-behind, manually controlled type.

Another object is to embody a novel tamping unit in the machine; such unit be ng power actuated and arranged to tamp an asphalt surface for the full width of the machine and at the immediate forward end of the latter.

A further object is to provide the machine with a roller assembly which effectively rolls the asphalt surface in trailing relation to the tamping unit; the roller assembly having no lateral projection relative to said unit in order to prevent rolling of untamped asphalt.

An additional object is to provide a novel drive mechanism between the motor and the front roller unit, as well as between said motor and the tamping unit; said drive mechanism being regulated by the operator, from his walk-behind station, by means of remote control devices on one of the handles which the machine includes.

A still further object is to provide an asphalt tamping machine, of the type described, which embodies novel mechanism to vertically adjust the tamping unit; the latter including tamping feet of a most effective design.

It is also an object of the invention to provide an asphalt compacting machine designed for ease and economy of manufacture.

A further object of the invention is to produce a practical and reliable mach ne and one which will be exceedingly eifective for the purpose for which it is designed.

These objects are accomplished by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claim.

In the drawings:

Figure 1 is a s de elevation of the machine; the housing being broken away in part.

Figure 2 is a fragmentary sectional elevation of the machine.

Figure 3 is a fragmentary sectional plan view showing, in part, the clutch controlled reversingdrive for the machine.

Figure l is a fragmentary sectional plan view of the front roller unit.

Figure 5 is a fragmentary, diagrammatic plan view of the machine with the housing removed.

Figure 6 is a fragmentary rear elevation showing the rockable mount for the transverse attachment bar of the rear roller unit.

Figure '7 shows the shiftable control arm for changing direction of travel.

Referring now more particularly to the characters of reference on the drawings, the asphalt compacting machine is relatively small, portable, and comprises a main frame, indicated generally at i, such main frame having a front cross bar 2 and a rear cross bar 3 included therein.

At the forward portion thereof the main frame :1 includes a central, longitudinal mounting plate 5.- which depends vertically from said frame.

The machine is supported, adjacent its forward end, by a front roller unit, indicated generally at 5, which roller unit is mounted in connection with the plate 4, as follows:

The plate l is fitted with a horizontal transversely extending bearing sleeve 6 through which a cross shaft 1 extends in turnable relation; such cross shaft being fitted at opposite end portions with rollers 8 keyed onto said shaft. The above described front roller unit 5 is driven in the manner as will hereinafter appear.

The machine is supported, adjacent its rear end, by a rear end roller unit, indicated generally at 9. Such rear end roller unit 9 comprises an open rectangular sub-frame ill in which a single rear roller It is journaled in a central position with respect to the sides of the machine, and such rear roller H thus traverses a path which laps the space between the front rollers 8 so that as the machine advances it rolls a path unbroken from side to side.

The rectangular subframe It includes, at the front thereof, a transverse attachment bar l2 which is secured in loose play relation to a cross bar it affixed to the rear end of the mounting plate 4 rearwardly of the rollers 8; the loose play connection being bolts I l which extend through vertically elongated slots l5 in the attachment bar l2. The loose play connection between the parts is such as to permit of limited up and down swinging adjustment of the sub-frame It) as well as limited rocking thereof in a transverse plane.

Relative up and down adjustment of the sub frame I0 is accomplished by means of a vertical screw shaft [6 threaded through a nut 61 carried in loose play relation in a cage l8 fixed on the sub-frame I 0; such screw shaft extending upwardly through the main frame l in rotatable but axially non-shiftable relation. At its upper end said screw shaft projects from said main frame upwardly through the top of a housing 19 which encloses the upper portion of the main frame and the hereinafter described mechanisms mounted thereon; the upper end of said screw shaft being fitted with a hand wheel 20. By manipulating the hand wheel 26 in one direction or the other, the sub-frame Ill is urged relatively upward or downward whereby to selectively alter the elevation of the front end of the machine as it rocks about the cross shaft 1 as an axis.

Ahead of the front roller unit 5, the machine is fitted with a tamping foot unit, indicated generally at 2|, which unit includes a pair of transversely elongated, surface tamping feet 22 symmetrically diagonal at adjacent ends with said ends lapping, whereby the tamping foot unit 2| is effective to tamp from side to side of the machine without any break. The effective tamplng width of the unit 2| is substantially the same as the effective rolling width of the hereinbefore described roller assembly; the latter having no lateral projection beyond the outer ends of said tamping foot unit 2 I.

Each tamping foot 22 is hollow with a multiplicity of perforations 23 through the bottom thereof; there being a fluid absorbent pad 24 in each foot overlying the perforations 23. As will be seen from Fig. 2, the bottom of the foot is in the form of a removable plate, removal of which gives access to the pad 24 for replacement if necessary, and also enables the perforations 23 to be readily cleaned out. A fluid, such as a relatively light lubricating oil, is fed as necessary and by means of an oil can or the like, into each hollow foot 22 through an intake port as shown in Fig. 2, saturating the pad 24 and slow-escaping through the perforations 23; the purpose being to lubricate the bottom of each foot 22 against asphalt adhering thereto. Similarly, a lubricant saturated pad 25 is mounted to run on each roller 3 to keep the latter clean.

A vertical plunger 26 is secured to each tamping foot 22 and extends upwardly through a guide sleeve 21 fixed on a transversely extending mounting bracket 25 of generally Z-shape which matchingly engages the front cross bar 2, being removably attached to the latter by bolts 29.

Each plunger 26 extends above the corresponding guide sleeve 21, and downward motion of each plunger is limited by a stop collar 30 adapted to strike a resilient or cushion washer 3| which surrounds the plunger between said collar and the upper end of the sleeve.

A heavy duty compression spring 32 surrounds each plunger 26 between the corresponding tamping foot 22 and the bracket 28; such spring being loaded with each upward motion of the plunger. The plungers 26 are recurringly raised and then released for forceful downward tamping motion by the loaded compression spring 32, as follows:

A longitudinal lever arm 33 is pivoted intermediate its ends rearwardly of each plunger 26 to the upper end of a swing post 34 upstanding from the bracket 28; the forward end of each lever arm 33 being pivoted to the related plunger while the rear end of each such arm is formed as a free, rearwardly projecting trigger 35.

The triggers 35 are recurringly engaged, depressed, and released by rotary actuators 36 on a cross shaft 31. Each rotary actuator includes spaced discs 38 having trigger engaging rollers 33 therebetween radially off-set from the shaft 31 in circumferentially spaced relation. The triggers 35 project into the rotary path of said rollers between the discs so as the actuators rotate, such triggers are recurringly engaged, depressed, and released by said rollers.

As will be obvious from Fig. 2, removal of the bottom plate of the foot may be eifected if the foot is lifted from the ground a distance considerably less than the stroke of the plunger 25. so that it is unnecessary to jack up the machine to perform the plate removing operation.

The cross shaft 31 is driven by an endless drive 40 from another cross shaft 4|; both of said cross shafts being journaled in the main frame I. The cross shaft 4| is driven by an endless drive 42 from an engine mounted on a platform 44 carried by forward horizontal portions of transversely spaced rearwardly projecting handles 45 which are secured to the rear of the main frame I for the purpose of manual steering or manipulation of the machine when it is in use.

The endless drive 40 is of belt type, and is adapted to be placed in operation by a belt tightener 46 controlled by a flexible wire, remote control device 41, which leads rearwardly up one handle 45 to a push-pull knob 48 adjacent the related hand grip 49.

With this arrangement, the tamping foot unit 2| can be placed in or out of operation at the selection of the operator by merely manipulating the push-pull knob 48.

The following driving mechanism is employed to reversibly drive the front roller unit 5:

An endless drive 56, including a sprocket 5| fixed to the inner end of one of the rollers 5. extends upwardly from said front roller unit 5: such endless drive 50 being actuated from its upper end by a counter-shaft 52 journaled transversely in the main frame I. In turn, the counter-shaft 52 is driven by the following clutch controlled reversing drive mechanism from the engine actuated cross shaft 4|:

As shown in detail in Fig. 3, the cross shaft 4| extends through a two-way clutch 53 whose shiftable part, which is slidably splined to said cross shaft 4|, is indicated at 54. The opposed rotary parts of the clutch 53, indicated at 55 and 56, respectively, are turnable on the cross-shaft 4|; the turnable clutch part 55 being connected to the counter-shaft 52 by meshing gears 51 while the turnable clutch part 56 is connected to said counter-shaft 52 by an endless drive 58. By shifting the clutch part 54 in one direction or the other, the above described arrangement imparts a selectively reversible drive to the counter-shaft 52 from the cross shaft 4|. In this manner the machine can be caused to selfpropel itself forwardly or rearwardly.

The shiftable part 54 of the clutch is adapted to be shifted one way or the other by a shifting fork arrangement 59 including upstanding trans versely swingable arms 60 secured at their upper ends to a longitudinal shaft 6| journaled in the main frame I from a top plate or deck 62 included therein.

At its rear end the longitudinal shaft 6| is fitted with a depending radial arm 63 adapted to be swung in one direction or the other by a flexible wire, remote control device 64 which extends from said arm 63 up the same handle 45 as the control device 41; the device 64 terminating at a push-pull knob 65 adjacent the pushpull knob 48. By manipulating the push-pull knob 65, the operator, from his walk-behind station, may cause shifting of the described clutch assembly to cause the machine to run forwardly or rearwardly.

As will be seen from Fig. 5, rollers 8 project laterally out from the frame structure; and the drive means for the rollers and tampers and ineluding belt drive 42, is contained between the planes of the outer ends of rollers 8. By reason of this fact, the rollers can work close to a curb or other vertical surface without any other part of the machine coming in contact with such surface.

Operation In the laying of asphalt surfaces, as on streets, parkways, etc., the large heavy-duty asphalt compacting and rolling machines cannot, because of their wide protuberances, gain access to the surface immediately adjacent a curb or wall. Heretofore it has been the practice to manually tamp and roll the asphalt strip which lies closely adjacent, such as a curb or wall. Not only would this produce an imperfect surface, but additionally was time and labor consuming.

With the present machine, such strip of asphalt can readily and quickly be tamped and rolled as the machine is small and designed without protuberances either forwardly or laterally. By manipulating the machine from his walk-behind station, and by means of the handles 45, the operator can cause the machine to run immediately adjacent a curb or wall with the tamping foot unit 21 in operation. Such unit tamps the strip of asphalt over which the machine is traveling, and such strip is then immediately rolled by the described roller assembly. By reason of its small compact design, its ready portability, and convenience of manipulation, the machine is operative for the intended purpose in a very efiicient and practical manner.

In order to adjust the tamping foot unit 2| to regulate the force of its blow on the surface being tamped, it is only necessary to run the hand wheel 20 in one direction or the other. Also, for transport, with the tamping foot unit 21 out of operation, the hand wheel 20 may be operated until such unit rises to a ground clearance position.

Under certain circumstances, it may be desired to use the machine solely as a roller in which event it is only necessary to remove the bolts 29 whereupon the mounting bracket 28, together with all the connected parts including the foot tamping unit 2 I, remove as a single assembly.

In addition to its very practical design for ready use the machine can be easily moved from job to job in a small truck, as such machine is of small size and thus capable of being loaded and unloaded without difliculty.

From the foregoing description it will be readily seen that there has been produced such a machine as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the machine, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claim.

Having thus described the invention, the following is claimed as new and useful and upon which Letters Patent is desired:

In an asphalt tamping machine having a frame, a tamping foot, a plunger projecting upwardly from the foot, a sleeve fixed on the frame through which the plunger intermediate its ends is slidable, a compression spring about the plunger between the sleeve and foot, a lever pivoted at one end on and projecting from the plunger at an angle thereto, a rotary driven unit on the frame to intermittently engage and depress the other end of the lever, and a substantially vertical link pivoted at one end on the lever intermediate its ends and at the other end on the frame; the foot being formed with an internal chamber having a perforated bottom plate, and an oil absorbing pad in the chamber resting on and covering the plate and leaving an oil .retaining space in the chamber above the pad, the foot having an oil intake port leading from exteriorly of the top to the top of the internal chamber.

JACK H. LUCAS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 544,746 Ober Aug. 20, 1895 732,826 Carter July 7, 1903 1,174,803 Bathrick Mar. 7, 1916 1,304,741 Cartwright May 27, 1919 1,442,057 Eggert Jan. 16, 1923 1,650,574 Stubbs Nov. 22, 1927 1,654,014 Proctor et al Dec. 27, 1927 1,684,574 Carlson Sept. 18, 1928 1,711,758 Stubbs May 7, 1929 1,744,272 LaPlant et a1. Jan. 21, 1930 1,819,866 Cameron Aug. 18, 1931 1,953,825 Finley Apr. 3, 1934 2,084,983 Baily June 29, 1937 2,098,895 Velten Nov. 9, 1937 2,109,851 Schumacher Mar. 1, 1938 2,116,816 Winkler May 10, 1938 2,132,059 Trembly Oct. 4, 1938 2,257,223 Borgman Sept. 30, 1941 2,382,986 Gauley Aug. 21, 1945 2,418,035 Lachapelle Mar. 25, 1947 FOREIGN PATENTS Number Country Date 66,731 Germany Oct. 27, 1938 

